Stenography is a widely used technique for recording the spoken word. The basic process includes two steps: (1) making a phonetic record of the speech being recorded, and (2) transcribing the phonetic record into a grammatical record such as, by way of example, an English language transcript. To ensure reliability and efficiency in the recording process, and to simplify the translating process, shorthand machines are frequently employed to produce the phonetic record. Such machines are especially useful when the recording is made over a relatively long period of time, for example in the courtroom or at a business meeting.
A widely used shorthand machine has a keyboard of twenty-two phonetically related symbols and characters which, to the skilled operator, provide the combinations necessary to record all English language words. The record produced by the machine is a paper tape on which the phonetic characters are printed. To record a word or part of a word, the operator strokes an appropriate combination of keys and the machine prints the characters simultaneously on an interval of the paper tape. The tape is advanced one interval after each combination is recorded.
For example, the paper tape record of the sentence, "You should be able to read these short words," would appear as follows on the paper tape:
______________________________________ U S H U D B A BL T O R E D T H E S S H O R T W O R DZ ______________________________________
A general description of this type of machine is given in U.S. Pat. No. 2,319,273 entitled "Stenographic Machine," issued to J. G. Sterling and assigned to the assignee of the present invention. The entire disclosure of U.S. Pat. No. 2,319,273 is incorporated herein by reference.
The shorthand machine provides both reliability and economy in the recording process. However, the translating process, while improved through the use of a shorthand machine, remains time consuming. The operator must read back the paper tape containing the phonetic characters and make a corresponding grammatical record.
U.S. Pat. Nos. 3,557,927; 4,205,351; and 3,832,733 describe improvements in the purely mechanical shorthand machine wherein the machine is modified to provide an electrical output in response to an operator engaging an appropriate combination of keys. The electrical output may be recorded on a computer-readable medium such as a floppy disk which may be read by a computer. The computer performs the translation by comparing the input characters from the shorthand machine with a grammatical reference stored in the computer's memory. In its simplest form, the grammatical reference is a "dictionary" which relates all English language words to their phonetic or machine shorthand equivalents.
By way of background it should be noted that the following terms are used throughout this disclosure and are to be given their intended meaning as understood in the art:
The term "stroke" refers to the act of an operator engaging the keys of a shorthand machine with sufficient force to impress a symbol or character on the paper tape, and/or to produce an electrical output representing the symbol.
The terms "symbol" and/or "character" mean any representation of word construction including but not limited to letters of an alphabet. The term "combination" is intended to include single as well as multiple elements.
The terms "phonetic words" and/or "shorthand notes" mean a particular combination of phonetic characters which may form all or part of the phonetics of a spoken word.
The terms "translated text", "language text" or "reader usable text" refer to the particular combination of characters that form a written word.
Computer programs that translate shorthand notes are referred to generally as computer-aided transcription ("CAT") systems. CAT systems, such as the OzPC made by Stenograph Corp., can be run on IBM and compatible PC's utilizing a DOS operating system. CAT dictionaries are stored in a look-up table in memory, and the shorthand notes are translated by searching through the look-up table. The basic look-up table begins by storing a number of equivalents in its memory locations. For example, a particular entry would indicate that the shorthand note "shud" is equal to the word "should." In performing a translation, the system would search through the look-up table to find the entry for "shud" and then output the equivalent grammatical word. Look-up tables can be organized and searched in a variety of known schemes, some examples of which include the "sequential", "hash" and "binary-tree" methods. These methods vary in speed, memory space and power requirements.
The binary-tree look-up table is the fastest of the three and the most efficient. Under a binary-tree approach, the computer performs an operation similar to searching for a name in the phone book. Looking for the name "Walter", the binary-tree does not simply start with the A's and plow through to the W's. Instead, it divides the book in half and asks itself which half Walter is in. This process is repeated for each appropriate half, further dividing the list until the matching item is found.
Although powerful, known CAT systems have constraints. For example, a PC is needed in order to perform the translation. Also, the recorded notes must be transferred from the shorthand machine to the PC which is usually remote from where the notes are originally transcribed.
A company known as "Digitext" has sold a shorthand machine that performs electronic translation and displays the translation one word at a time on a one-line LCD display. This machine is apparently designed as a teaching aid, and thus, does not have the general portability and flexibility that would be required for practical use. For example, the dictionary is stored in a relatively small and slow memory (approximately 10,000 entries) that is not user definable. Also, the Digitext device must be connected to an electrical outlet and is not provided with a manual mode or battery operation.
Thus, it is an object of this invention to provide a novel method of organizing and searching a look-up table.
It is another object of this invention to provide a shorthand machine capable of recording shorthand notes and translating these notes into user readable form.
It is another object of the present invention to provide a self-translating shorthand machine having a user updatable on-board translation dictionary.
It is another object of this invention to provide a flexible, portable and battery-operated shorthand machine with powerful and sophisticated display capabilities.
It is another object of this invention to provide a shorthand machine capable of performing computer aided translation and displaying the translation on several lines of an LCD.
It is another object of this invention to provide a novel method of organizing and searching a look-up table.